High volume liquid waste collection and disposal system

ABSTRACT

A system for collecting and disposing of liquid medical waste includes a fluid collection cart and a draining and cleaning station. The fluid collection cart includes a pair of containers, each of which includes a draining port and a cap. Each cap includes an outer portion having a flushing port and a bore formed therein and an inner portion having vacuum and patient ports formed therein. The inner cap portion is disposable and removably positioned within the bore of the outer cap portion. Liquid level detectors also communicate with each container. The cart also includes a regulator so a low vacuum level may be pulled on one of the containers while a full vacuum level is pulled on the other container. Fluids are collected in the containers via suction tubes connected to the patient ports. The flushing and drain ports of the containers are connected to corresponding flushing and drain connectors on the station when the containers are full so that they may be drained and flushed. The cart liquid level detectors communicate with the station microprocessor so that the draining and flushing cycles may be properly sequenced. The station may also clean suction canisters.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a division of presently pending application Ser. No.10/090,221, filed Mar. 4, 2002 now U.S. Pat. No. 6,893,425B2.

BACKGROUND OF THE INVENTION

I. Field of the Invention

The present invention relates generally to systems for handlingbiological fluids and, in particular, to a system for collecting a largevolume of liquid waste during a medical procedure and safely disposingof the waste.

II. Description of the Related Art

Various forms of liquid medical wastes are commonly produced in surgeryand other medical procedures. Such wastes may include blood and otherbody fluids of patients. The wastes may also include solid particlessuch as fragments of bone or cartilage. Some procedures produce a highvolume of such waste from a single patient. For example, saline solutionis used to irrigate the knee area during arthroscopic procedures. Asanother example, saline solution is used to flush the bladder, urethraand/or prostate in some urology procedures. Such procedures may produceas much as 30,000 cc of liquid medical waste.

Liquid medical waste generates significant disposal problems due to itspossible contamination with various infectious diseases, including AIDS,hepatitis and MRSA. As a result, rules and regulations for the handlingand disposal of liquid medical waste have been imposed by variousgovernmental and regulatory agencies. For example, new regulationsrequire the use of engineering controls to protect employees fromexposure. In addition, hospitals and other health care facilities havebeen searching for methods and systems that reduce hospital personnel'sexposure to the fluids during collection, handling and disposal.Procedures that produce large volumes of liquid medical waste amplifythese issues and concerns.

Various systems and methods have been used for collecting, handling anddisposing of fluids from procedures that produce large volumes of liquidmedical waste. The collection vessels vary from simple buckets toautomated, electronically controlled processing equipment.

A bucket, referred to as a “gravity bucket”, may be placed by anoperating room table or placed in another convenient location within theroom in which a medical procedure is being performed. Flexible tubingtypically connects the gravity bucket with the region of the patientfrom which the fluid wastes are collected. When the gravity bucketbecomes filled, it is carried out of the operating room and its contentsare poured down a drain. Such an arrangement has several drawbacks.Carrying the open bucket and emptying it manually creates theopportunity for direct human contact with the potentially infectedwastes if the fluid spills or leaks from the bucket. In addition, thefluids may splash back or otherwise result in the formation of aerosolsthat contact the person disposing of the waste.

Suction canisters are commonly used to aspirate fluids from patientsduring surgical procedures. Such canisters range in volume from around1200 cc to around 3000 cc. A suction canister typically features aremovable lid with a vacuum port and a patient or suction port. During asurgical procedure, the vacuum port is connected by flexible tubing to ahospital vacuum source while the suction port is connected by a secondflexible tube to the region of the patient from which the fluid wastesare collected.

As an alternative to a gravity bucket, a number of suction canisters maybe positioned on a stand and connected in tandem. The stand features abase positioned on rollers so that the stand may be rolled to, from andaround an operating room. A vertical rod extends upwards from the baseand has a number of horizontal rings connected thereto. Each ring issized to hold a suction canister and the rings are positioned on thevertical rod in a spaced and staggered fashion. The eight (for example)canisters positioned on the stand are connected in a tandem fashion asfollows. The first canister has its suction port connected to thepatient's surgery site by a flexible tube. The vacuum port of the firstcanister is connected to the suction port of a neighboring secondcanister. The vacuum port of the second canister is connected to thesuction port of a third canister. The arrangement is repeated for thefourth through seventh canisters. The eighth canister suction port isconnected to the vacuum port of the seventh canister while the vacuumport of the eighth canister is connected to the hospital vacuum source.As a result, each of the eight canisters is subjected to suction so thatfluids produced by the medical procedure are collected in the canisters.

While such an arrangement allows a large volume of fluid to becollected, as the above description reveals, the connection of thecanisters is complicated. If one mistake is made in connecting thetubing, no suction is available for the procedure. In addition, thestand becomes somewhat top heavy with the canisters filled so that thecart becomes difficult to maneuver and great care must be exercised whenmoving the cart. The arrangement also results in a large number ofcanisters to clean or dispose of as infectious waste. Using the aboveexample, one procedure would result in eight canisters that need to bedumped and cleaned. This is very time consuming. The large number ofcanisters required also makes the arrangement expensive.

Systems for collecting and disposing of high volumes of fluids areoffered by the Steris Corporation of Mentor, Ohio, as the “SafeCycle40”, and Stryker Instruments of Kalamazoo, Mich., as the “Neptune WasteManagement System.”

The Steris “SafeCycle 40” system, described in U.S. Pat. Nos. 4,863,446and 4,957,491, both to Parker, is a fluid collection and disposal systemfeaturing a mobile fluid collection cart and a disposal station. Thefluid collection cart includes vacuum and suction ports that communicatewith a reservoir that is positioned on the cart. The reservoir alsofeatures a drain outlet. A vacuum line connects the vacuum port of thecollection cart to a hospital vacuum source during surgery so that fluidis withdrawn from the patient via flexible tubing that is connected tothe cart's suction port and collected in the reservoir. The collectioncart features a vacuum regulator that permits the level of suctionprovided by the cart suction ports to be adjusted by knobs on the cart.After surgery, the collection cart is connected to the disposal stationvia washing and draining connectors so that the reservoir is drained andflushed via a timed cleaning process.

The Stryker “Neptune” system, described in U.S. Pat. Nos. 5,997,733 and6,180,000, both to Wilbur et al., is a portable waste disposal systemthat includes a waste collection system, a smoke extraction system and atreatment and disposal system that heats the waste to sanitize it fordisposal. The system includes a container that features a vacuum portthat is connected to a vacuum source of a hospital. The container alsoincludes a suction port that is in communication with the patientsurgery site via flexible tubing. As a result, fluids from the patientare collected in the container. Smoke is withdrawn from the patientsurgery site by an additional flexible tube that is in communicationwith the head space of the container. The smoke is filtered as it iswithdrawn from the head space into a housing that contains additionalfilters and a fan that pulls the smoke into the housing. The containeralso includes a drain which may either be connected to the treatmentsystem or a hospital drain so that the fluid in the container may bedrained or treated and then drained.

While the Steris and Stryker systems have proven to be effective, thesystems are unable to accommodate suction canisters of the 1200 cc to3000 cc variety. As a result, a separate cleaning and disposal systemfor the smaller suction canisters must be purchased by a hospital inaddition to the Steris and Stryker machines. This results in an increasein purchase expenses and personnel training for a hospital or otherhealth care facility. The requirement for two separate systems alsoresults in increased maintenance costs. Due to their complexity, theSteris and Stryker systems are also quite costly. Also due to theircomplexity, at least in part, the carts of the Steris and Strykersystems are heavy when their containers are full. This makes pushing andmaneuvering the carts burdensome.

Accordingly, it is an object of the present invention to provide asystem for safely and conveniently collecting a large volume of liquidwaste during a medical procedure.

It is another object of the present invention to provide a system thatpermits large volumes of liquid medical waste to be handled and disposedof without contact by personnel.

It is another object of the present invention to provide a system thatsimultaneously provides both high and low or gravity drain suction.

It is another object of the present invention to provide a system forcollecting, handling and disposing of large volumes of liquid medicalwaste that is economical to purchase and maintain.

It is still another object of the present invention to provide a systemfor collecting, handling and disposing of large volumes of liquidmedical waste that is easy to configure and operate.

It is still another object of the present invention to provide a systemthat facilitates handling of large volumes of liquid medical waste.

It is still another object of the present invention to provide a systemthat accommodates both large volume containers and smaller, individualsuction canisters.

It is still another object of the present invention to provide a systemfor collecting, handling and disposing of large volumes of liquidmedical waste that may also withdraw smoke from a patient's surgicalsite.

Other objects and advantages will be apparent from the remaining portionof this specification.

SUMMARY OF THE INVENTION

A system for collecting and disposing of liquid medical waste includes acart for collecting medical waste and a station for draining andcleaning the containers of the cart. The cart includes a body supportedby a plurality of wheels. First and second containers are mounted on thecart body and each has a drain port and cap positioned thereon. Each capincludes an inner portion and an outer portion. The inner cap portionhas a patient port and a vacuum port formed therein. The outer capportion has a bore formed therein within which the inner cap portion isremovably received. A flushing port is also formed in the outer capportion. A cleaning nozzle is positioned within the container and is incommunication with the flushing port. Filters, including possibly anoptional smoke plume filter, communicate with each container vacuumport. Liquid level detectors also communicate with the containers.

The cart also includes a vacuum regulator positioned thereon. Theregulator selectively communicates with the vacuum port of one of thecontainers and a hospital vacuum source so that a low vacuum level maybe pulled on the container. The vacuum port of the other containerbypasses the regulator so that a full vacuum level is simultaneouslypulled on the unregulated container. A housing defining a chamber withinwhich the vacuum regulator is positioned features a control panel withvalve handles so that the vacuums pulled by the containers may becontrolled. Suction lines are attached to the patient ports of thecontainers so that liquid medical waste is drawn into each container asthe vacuums are pulled thereon.

Flushing connectors are in communication with the flushing ports of thecontainers, drain connectors are in communication with the drain portsof the containers and electrical connectors are in communication withthe liquid level detectors. The flushing, drain and electricalconnectors are mounted on a side panel of the cart for connection tocorresponding connectors on the draining and cleaning station after thecart containers have been filled during a medical procedure. Whenconnected to the draining and cleaning station, the cart containers aredrained and flushed. The collected medical waste in the containers maybe detected via the liquid level detectors by the station microprocessorwhen the liquid level detector is placed in communication with thestation through the electrical connectors. As a result, themicroprocessor can control the sequencing of the container draining andflushing cycles. The draining and cleaning station may also be used toclean suction canisters.

The following detailed description of embodiments of the invention,taken in conjunction with the appended claims and accompanying drawings,provide a more complete understanding of the nature and scope of theinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a fluid collection cart of an embodimentof the system of the present invention;

FIG. 2 is a side elevation view of the cart of FIG. 1;

FIG. 3 is a sectional view of the cart of FIG. 2 taken along line 3—3;

FIG. 4 is a schematic view of the regulator housing of the cart of FIGS.1–3;

FIG. 5 is an enlarged perspective view of one of the containers of thecart of FIGS. 1–3;

FIG. 6 is an exploded top plan view of the container cap of FIG. 5;

FIG. 7 is a partially broken-away side elevation view of the containerof FIG. 5;

FIG. 8. is a sectional view of the container of FIG. 7 taken along line8—8;

FIG. 9 is a partially broken-away perspective view of the cart of FIG. 1connected to a draining and cleaning station;

FIG. 10 is a schematic view of the draining and cleaning station of FIG.9;

FIG. 11 is a flow diagram showing the steps of the software program ofthe microprocessor of FIG. 10.

DETAILED DESCRIPTION OF THE INVENTION

The fluid collection cart of a preferred embodiment of the system of thepresent invention is indicated in general at 12 in FIGS. 1–3. The cartfeatures a cabinet-like body 14 that is supported at its bottom fourcorners by wheels 16. Opposing handles 18 a and 18 b are secured to thetop of the cart body 14 to facilitate pushing, pulling and maneuveringof the cart. The cart 12 is preferably constructed of plastic forstrength, durability and light weight.

The cart body 14 defines an interior space 22 within which a shelf 24 ismounted. While not illustrated, doors may optionally be provided on thecart so that the interior space 22 is hidden from view when the doorsare closed. Shelf 24 features a pair of openings 26 a and 26 b formedtherein within which bottle-shaped containers 32 a and 32 b are secured.Containers 32 a and 32 b are preferably constructed of glass for ease ofcleaning and are sized to hold approximately six gallons of liquid each.

As illustrated in FIGS. 2 and 3, the bottom of each container 32 a and32 b is provided with a drain port, 34 a and 34 b, respectively. Asillustrated in FIG. 2, drain port 34 b is connected to the inlet of adrain valve 36 by line 42. The outlet of drain valve 36 communicates byline 44 with a drain connector, illustrated at 46 b in FIG. 1. Bothdrain valve 36 and drain connector 46 b are mounted to a side panel 52of cart 12. Drain valve 36 may be opened or closed by drain valve handle48 b. When drain valve 36 is closed, communication between the drainconnector 46 b and the drain port 34 b of container 32 b is prevented.When drain valve 36 is open, fluid within container 32 b flows to drainconnector 46 b. Drain connector 46 a is connected to drain port 34 a ofcontainer 32 a in a similar fashion through a valve (not shown) that iscontrolled by drain valve handle 48 a. The associated tubing has beenomitted from FIG. 2 for the sake of clarity. In addition, all tubing hasbeen omitted from FIG. 3 for the sake of clarity. Drain valve handles 48a and 48 b are configured so that their corresponding valves are closedwhen the cart is used during a medical procedure to collect biologicalfluids.

The tops of containers 32 a and 32 b are closed by caps 54 a and 54 b,respectively, which extend through the top surface 55 of cart body 14.Caps 54 a and 54 b preferably are constructed of plastic and featurevacuum ports 56 a and 56 b and patient or suction ports 58 a and 58 b.As illustrated in FIG. 2, the suction ports 58 a and 58 b are connectedto flexible tubing suction lines 62 a and 62 b which lead to the regionof the patient from which the fluid wastes are collected. Fluids arewithdrawn from the patent via tubing 62 a and 62 b and collected incontainers 32 a and 32 b, respectively, when vacuums are pulled on thecontainers via vacuum ports 56 a and 56 b. Vacuum ports 56 a and 56 bare connected via flexible tubing 64 a and 64 b, respectively, to aregulator housing 72 that is mounted upon the top surface 55 of the cartbody 14. As illustrated in FIG. 8, the vacuum port is equipped with aPorex filter 146 that, in addition to filtering (as will be describedbelow), may cooperate with the hospital vacuum source to automaticallystop suction when the canister is full.

As illustrated in FIG. 4, housing 72 defines a chamber 74 that featuresa regulator 76 preferably set to 5 in. Hg and associated valves andpiping. More specifically, line 64 a leads to regulator 76. A vacuumsource line 82 is connected to a hospital vacuum source and communicateswith regulator 76 through check valve 84 and control valve 86. A bypassline 92 connects line 82 with line 64 a through bypass valve 94. Asecond vacuum source line 96 may be placed in communication with asecond hospital vacuum source and communicates with line 64 b andcrossover line 98 through check valve 102. Crossover line 98 is equippedwith control valve 104 and communicates with hospital vacuum source line82.

As illustrated in FIG. 1, housing 72 features a control panel 106featuring valve handles 108 a, 108 b and 110. All three valve handlesmay be manipulated between two positions. Valve handles 108 a and 108 bmay both be toggled between “open” and “closed” settings. Valve handle110 may be toggled between “full” and “low/gravity drain” settings.Valve handle 108 a configures control valve 86 of FIG. 4 between theopen and closed positions, valve handle 108 b configures control valve104 of FIG. 4 between the open and closed positions and valve handle 110configures control valve 94 of FIG. 4. The “full” setting of valvehandle 110 corresponds to an open condition for bypass valve 94 and a“low/gravity drain” setting of valve handle 110 corresponds to a closedcondition for bypass valve 94.

The operating mode of the cart during a medical procedure depends uponthe configuration of valve handles 108 a, 108 b and 110 and whether oneor both of vacuum source lines 82 and 96 are connected to hospitalvacuum sources. Taking first the situation where only vacuum source line82 is connected to a hospital vacuum source, a full vacuum ofapproximately 25 in. Hg is pulled on container 32 b through lines 64 b,98 and 82, as illustrated by arrows 112 and 114, when valve 104 isopened (via valve handle 108 b of FIG. 1).

With the cart connected to a single hospital vacuum source through line82, and a full vacuum being pulled on container 32 b, container 32 a maysimultaneously pull a low or gravity drain vacuum of approximately 5 in.Hg when valve handle 108 a (FIG. 1) is placed in the “open” position, sothat valve 86 is open, and valve handle 110 is placed in the“low/gravity drain” position so that bypass valve 94 is closed. Withreference to FIG. 4, this results in a vacuum being pulled on line 64 a,as illustrated by arrow 116, and thus container 32 a, by line 82 throughregulator 76 so that the vacuum pulled on line 64 a and container 32 ais limited by regulator 76 to 5 in. Hg. As a result, the system of thepresent invention provides for both high level suction and gravity drainvia suction lines 62 b and 62 a (FIG. 2), simultaneously during amedical procedure.

If valve 104 is shut, by placing corresponding valve handle 108 b ofFIG. 1 in the “closed” position, no vacuum is pulled on container 32 band either a low vacuum of approximately 5 in. Hg or a high vacuum ofapproximately 25 in. Hg may be pulled on container 32 a by togglingvalve handle 110 between the “low/gravity drain” and “full” positions,respectively. With valve handle 110 set to the “full” position, bypassvalve 94 is opened so that the vacuum pulled on line 64 a, and thuscanister 32 a, by line 82 bypasses regulator 76. Of course, valve 86must be open, with corresponding valve handle 108 a of FIG. 1 placed inthe “open” position.

If both lines 82 and 96 are connected to hospital vacuum sources, andvalves 86, 104 and 94 are open, a full vacuum of approximately 25 in. Hgis pulled on each container 32 a and 32 b.

As illustrated at 120 a and 120 b in FIGS. 1–3, a liquid level detectoris positioned on the bottom of each container 32 a and 32 b. While otherdevices known in the art may be used, liquid level detectors 120 a and120 b preferably are capacitance sensors. As illustrated in FIG. 2,capacitance sensor 120 b is connected to electrical connector 122 b,shown mounted to the cart body side panel 52 in FIG. 1, by electricalline 124. Sensor 120 a is connected to electrical connector 122 a ofFIG. 1 in a similar fashion, however, the corresponding electrical linehas been omitted from FIG. 2 for the sake of clarity. As will beexplained below, the sensors 120 a and 120 b and electrical connectors122 a and 122 b, along with drain connectors 46 a and 46 b, find useduring the draining and flushing or cleaning cycles.

Enlarged and detailed views of container 32 b are presented in FIGS. 5,7 and 8. It is to be understood that container 32 a features anidentical construction. As illustrated in FIGS. 5–8, plastic cap 54 bincludes an outer portion 130 and an inner portion 132. As illustratedin FIGS. 7 and 8, the outer portion 130 of cap 54 b features a downwardextending skirt 133 with a threaded inner surface 134. The outer capportion 130 screws onto the threaded top opening 136 of container 32 bvia threaded inner surface 134 and also features a bore 138.

The inner portion 132 of cap 54 b features vacuum port 56 b and patientor suction port 58 b formed in its circular surface 141. In addition, asillustrated in FIG. 6, inner cap portion 132 has a pair of opposing tabs142 a and 142 b formed on its circumference 144. Correspondinghorizontal slots 145 a and 145 b are formed in the bore 138 of outer capportion 130. A pair of vertical channels 147 a and 147 b correspondingto the width of the tabs are formed between the top surface of the outercap portion 130 and the horizontal slots 145 a and 145 b. As a result,as indicated by dashed arrow 149 in FIG. 6, the tabs 142 a and 142 b ofthe inner cap portion 132 may be lowered via the vertical channels 147 aand 147 b into the horizontal slots 145 a and 145 b and turned in thedirection indicated by arrow 151 so that the inner cap portion 132 islocked within the bore 138 of the outer cap portion 130.

As a result, inner cap portion 132 may be removed from the outer capportion 130 for disposal after use. This is desirable in thatpotentially contaminated biological fluids from a medical procedure flowthrough suction port 58 b during a medical procedure. In addition, asillustrated in FIG. 8, the vacuum port 56 b is provided with a Porexfilter 146. This prevents bacteria and fluids from entering the hospitalvacuum source. It is thus desirable to dispose of the Porex filter afteruse. This is also accomplished by disposing of the inner cap portion132.

It should be noted that other temporary inner cap portion fasteningarrangements may be substituted for the one illustrated in FIG. 6. Forexample, bore 138 of outer cap portion 130 and the circumference 144 ofinner cap portion 132 could be provided with mating threads so that theinner cap portion is screwed into the bore of the outer cap portion.

During a surgical procedure, the surgical site of a patient may undergoprocedures that produce smoke. Examples of such procedures includecauterizing and drilling. Such smoke contains foul smelling andpotentially infectious airborne particles. As a result, for sanitaryreasons, such smoke must removed from the patient's surgical site. Asillustrated in phantom at 152 in FIG. 8, a smoke plume filter mayoptionally be connected to vacuum port 56 b so as to be in series withline 64 b of FIGS. 1 and 2. Such filters are known in the art and permitthe canister 32 b to collect smoke from a patient's surgery site viasuction tube 62 b of FIG. 2. In order to accomplish this, full suction(approximately 25 in. Hg) must be pulled on canister 32 b.

As illustrated in FIGS. 5–7, the outer cap portion 130 is equipped witha flushing port 154. As illustrated in FIG. 7, the flushing port 154communicates with a conduit 156, preferably constructed of plastic, thatextends down into the interior of container 32 b. Positioned on the endof conduit 156 is a cleaning nozzle, illustrated at 162 in FIG. 8.Cleaning nozzle 162 preferably rotates when liquid is supplied theretoso that water and cleaning solution flowing to the nozzle is sprayedonto the interior surfaces of container 32 b.

In some instances, the spray provided by nozzle 162 causes the pressurewithin container 32 b to increase rapidly. The increased pressure withinthe container 32 b causes liquid to back up in conduit 156, sometimes ashigh as six to eight inches. To combat this occurrence, a “top hat”shaped piece 163 may optionally be added to conduit 156 so as to extendbelow the nozzle 162. The top hat piece features a number of orifices164 through which liquid from the conduit flows. The liquid thencascades over the brim 166 of the top hat piece. As a result, thepressure head within the container 32 b is collapsed so that the back upof liquid into conduit 156 does not occur.

With reference to FIGS. 1 and 2, the flushing port 154 is connected to aflushing connector 168 b via flexible tubing 172. The flushing port ofthe cap of container 32 a is connected to the flushing connector 168 aof FIG. 1 in a similar fashion. Both flushing connectors 168 a and 168 bare mounted to the side panel 52 of cart body 14. As with electricalconnectors 122 a and 122 b and drain connectors 46 a and 46 b, theflushing connectors 168 a and 168 b find use during the draining andcleaning cycles which now will be described. The flushing connectors 168a and 168 b feature integral valves that seal when the connectors arenot connected to lines so that vacuums may be pulled within containers32 a and 32 b during fluid collection.

After a medical procedure is completed, or the containers 32 a and 32 bare filled, lines 82 and 96 (FIG. 1) are disconnected from the hospitalvacuum source(s) and suction lines 62 a and 62 b (FIG. 2) aredisconnected from the suction ports 58 a and 58 b. Caps are then placedupon the suction ports and the cart is wheeled out of the operating roomto a separate room containing the draining and cleaning station. As willbe described below, a modified version of the “RedAway II” system soldby Domoch Medical Systems, Inc. of Riverside, Mo. may be used as thedraining and cleaning station for the cart. The RedAway II system isdescribed in detail in pending U.S. patent application Ser. No.09/870,215, the contents of which are incorporated herein by reference.

FIG. 9 illustrates the cart 12 connected to the draining and cleaningstation, indicated in general at 173, so that the container 32 b of cart12 may be drained and cleaned. Similar to cart 12, draining and cleaningstation 173 features electrical, flushing and drain connectors,illustrated at 174, 176 and 178, respectively. As illustrated in FIG. 9,the electrical, flushing and drain connectors of the cart, 122 b, 168 band 46 b, are each connected to the corresponding connectors positionedon the housing 181 of cleaning station 173 by line 182 and flexibletubing 184 and 186, respectively. After these connections are made,drain valve handle 48 b is opened. The entire draining and cleaningprocess may now be controlled from the control panel 188 of the station173.

As illustrated in FIG. 10, the draining and cleaning station 173includes a microprocessor 192 that communicates with capacitance sensor120 b via electrical connectors 174, 122 b, line 182 and line 124 (FIG.2). The microprocessor also communicates with the control panel 188 ofthe cleaning station as well as a drain pump 194 and a flushing pump196. The flushing pump inlet is in communication with a water supplysource 202. A dispenser 204 containing a supply of bleach 206, or otheradditive, is positioned within the draining and cleaning station cabinet181 and also communicates with the water supply source 202 and the inletof flushing pump 194. The drain pump communicates with the hospital orhealth care facility drainage system 208. The drain and flushing pumps196 and 194 also communicate with the drain and flushing connectors 178and 176.

Microprocessor 192 also communicates with an automated control valve197. Control valve 197 may be configured to route the mixture of bleachand water from pump 194 to either flushing connector 176 or spray jets234 and 236, which are positioned in the sink 224 of the station. Themicroprocessor also communicates with the draining and cleaning stationcanister handling mechanism 199. As will be explained below, thesecomponents permit the draining and cleaning station to drain and flushsuction canisters and are disabled when the station is draining andflushing the containers of cart 12.

The processing performed by the microprocessor 192 of FIG. 10 isillustrated in FIG. 11. When the draining cycle is initiated by a“start” button on control panel 188, the microprocessor first checks forthe presence of liquid waste in container 32 b via capacitance sensor120 b (FIGS. 1–3). If liquid waste is in container 32 b, as will bediscussed in greater detail below, the microprocessor reconfigures valve197 and disables canister handling mechanism 199. The microprocessoralso illuminates a “drain cycle” indicator light on the control panel188 and activates drain pump 196 so that the contents of the containerare drained through line 42 (FIG. 2), line 186 (FIG. 9) and directed tothe drain system 208.

When the capacitance sensor 120 b (FIGS. 1–3) indicates to themicroprocessor that the liquid waste has been drained from thecontainer, flushing pump 194 is activated. The “drain cycle” indicatorlight on panel 188 is also extinguished and a “flushing cycle” indicatorlight is illuminated. Flushing pump 194 sends a stream consisting of amixture of water and bleach, from water source 202 and dispenser 204,respectively, through lines 184 and 172 (FIG. 9) to the flushing port154 of the cap 54 b of container 32 b. As a result, the interior ofcontainer 32 b is sprayed with the water and bleach mixture by thenozzle 162 of FIG. 8. Drain pump 196 remains activated so that themixture of bleach, water and residue is withdrawn from the container anddirected to drain system 208.

After a period of time, the flushing pump is deactivated. The drain pumpcontinues to run so that all of the liquid in container 32 b drains.When the capacitance sensor 120 b indicates that the container is empty,the flushing pump is once again activated so that the flushing cycle isrepeated. Microprocessor 192 keeps track of the number of flushingcycles performed by using, for example, the cycle counter included inFIG. 11. Preferably, two or three flushing cycles are performed. Whenthe last flushing cycle is performed, the “flushing cycle” light oncontrol panel 188 is extinguished and the drain pump is deactivated. Thedraining and flushing cycles are then completed. Container 32 b is thenprepared for reuse by the removal and disposal of the inner cap portion132 (FIGS. 5–8). A new replacement inner cap portion 132 is theninstalled.

Once draining and flushing of container 32 b is completed, the drainvalve handle 48 b is closed and the connectors 174, 176 and 178 ofstation 173 are disconnected from connectors 122 b, 168 b and 46 b. Thestation connectors are then reconnected to cart connectors 122 a, 168 aand 46 a and drain valve handle 48 a is opened so that container 32 amay be drained and flushed.

As described in U.S. application Ser. No. 09/870,215, when cart 12 isnot present, the draining and cleaning station may alternatively be usedto clean suction canisters. With reference to FIG. 9, a filled canister220 is placed within a bracket 222 which is secured within sink 224which is positioned within the housing 181 of the station. After the lid226 of the station is closed, and the “start” button on control panel188 is pressed, the lid 228 of the canister is automatically removed andthe canister is rotated about a horizontal axis by the canister handlingmechanism (199 in FIG. 10). The contents of the canister then drain intothe sink 224 and down drains 232 and 208 (FIGS. 9 and 10). Spray jets234 and 236 then spray the inverted canister with a mixture of bleachand water (FIGS. 9 and 10). As illustrated in FIG. 11, when thecapacitance sensor of cart 12 is connected to the draining and cleaningstation 173, and the station “start” button is pressed, themicroprocessor of the station recognizes the presence a filled cartcontainer and reconfigures valve 197 of FIG. 10 so that liquid from thepump is directed to connector 176 and the canister handling mechanism199 is also disabled so that the canister cleaning operation cannot beperformed.

While FIGS. 9–11 are described with respect to the draining and cleaningmachine of U.S. patent application Ser. No. 09/870,215, other canisterdraining and cleaning stations or systems may be easily modified toclean the containers of cart 12. These stations include thoseillustrated in U.S. Pat. Nos. 6,263,887 and 5,901,717, the latter ofwhich is sold by Dornoch Medical Systems, Inc. as the “RedAway I”system. Both patents are also owned by Dornoch Medical Systems, Inc.

While the preferred embodiments of the invention have been shown anddescribed, it will be apparent to those skilled in the art that changesand modifications may be made therein without departing from the spiritof the invention, the scope of which is defined by the appended claims.

1. A removable and disposable inner cap portion for a cap of a containerfor collecting medical waste, where the cap has an outer cap portionwith a bore formed therein, the disposable inner cap comprising: a) acircular surface with a vacuum port and a patient port formed therein;and b) means for removably securing the inner cap portion within thebore of the outer cap portion; whereby said vacuum port is adapted to beconnected to a vacuum source and said patient port is adapted to beconnected to a suction line so that medical waste may be collected inthe container through the suction line and the patient port when avacuum is pulled on the container through the vacuum port and thedisposable inner cap may be disposed of after the vacuum port andpatient port are disconnected from the vacuum source and the suctionline, respectively, so that medical waste on the disposable inner cap isalso disposed of.
 2. The removable inner cap portion of claim 1 whereinthe bore has a horizontal slot formed therein and the means forremovably securing the inner cap portion within the bore of the outercap portion includes a tab positioned on the circumference of the innercap portion where said tab is sized to engage the horizontal slot of thebore of the outer cap portion.
 3. The removable inner cap portion ofclaim 1 further comprising a filter in communication with the vacuumport.
 4. The removable inner cap portion of claim 3 further comprising asecond filter in communication with the vacuum port for filtering smoke.